To explore the application effect of UAV LiDAR in beach topography measurement in the Yangtze Estuary waters,UAV LiDAR field measurements are carried out in different areas of the Yangtze Estuary waters on the basis of exploring the principle of UAV LiDAR measurement.Through data calculation and comparative analysis,it is found that the measured data are greatly affected by the vegetation cover of the mudflat,which makes it difficult to read the mudline of the mud flat.Selecting colder seasons such as autumn and winter to carry out UAV LiDAR measurements is conducive to improving the accuracy of the data,while some areas covered with good perennial vegetation are recommended to be measured by multiple flights to improve the effective data volume.In addition,when carrying out UAV LiDAR data measurements,it is necessary to synchronize traditional means such as GNSS-RTK measurements to verify the accuracy of the data,and the combination of UAV photographic data is conducive to the discrimination of various types of feature elements.